On Thursday the sheriff's office corrected an earlier statement asserting deputies were not aware of the videos when they checked on Rodger on April 30.

On May 23, Rodger, 22, killed six people and then himself in Isla Vista, Calif.

In the homemade videos, Rodger filmed himself talking about his feelings of loneliness, being wronged by women who did not like him and wanting to "punish you all for it," according to one of his videos.

The sheriff's department also revealed new details on the timing of the incidents leading up to the rampage.

At 9:17 p.m. on May 23, Rodger uploaded his final video to YouTube detailing his "Day of Retribution" and reasons for killing. One minute later, he e-mailed a lengthy manifesto to his parents and therapist.

The first gunshots were reported at 9:27 p.m. and Rodger was dead eight minutes later.

In the manifesto, Rodger revealed he had removed most of his YouTube videos after the deputies visited him.

Rodger wrote that when the deputies visited him, they asked him if he had suicidal thoughts. "I tactfully told them that it was all a misunderstanding and they finally left. If they had demanded to search my room that would have ended everything," he wrote.

The sheriff's department did not explain why the deputies did not watch the videos, or how deputies became aware of the videos in the first place.

A family friend told the Los Angeles Times that Rodger's mother had contacted his therapist about the videos on YouTube. The therapist then contacted a mental health service, who reached out to police, the Times reports.